JP7469303B2 - Film forming equipment - Google Patents

Description

The present invention relates to a film forming apparatus.

An optical film is formed on an optical device, and this optical film reflects light in a specific wavelength range and transmits light in other wavelength ranges. Examples of optical devices include cold mirrors such as liquid crystal projectors, copiers, and focusing mirrors of infrared sensors. A cold mirror is formed with a laminated film that serves as an optical film that reflects visible light and transmits light in a specific wavelength range. A known method for forming such a laminated film is a sputtering method in which a target made of a film-forming material is exposed to plasma to knock out particles that make up the target, and the particles are deposited on a workpiece.

JP 2005-266538 A

It is known that the laminated film formed by sputtering has uneven surfaces due to the occurrence of sparse and dense areas of the deposited particles. In laminated films that become optical films by stacking films with such uneven surfaces, diffuse reflection of light occurs at the interfaces between the films, and optical properties such as transmittance can deteriorate.

The present invention has been made to solve the above-mentioned problems, and its object is to provide a film forming apparatus capable of forming a flat film while suppressing deterioration of optical properties.

a film forming unit for forming a film on a workpiece, the film forming unit comprising: a chamber capable of evacuating the inside; a transport unit provided within the chamber and having a rotary table for circulating and transporting the workpiece on a circumferential transport path; a target made of a material for forming the film; and a plasma generator for converting a sputtering gas introduced between the target and the rotary table into plasma, the film forming unit forming a film on the workpiece by sputtering the target with the plasma; a cylindrical body protruding into the internal space of the chamber and opening toward the transport path; a window member provided to close the opening of the cylindrical body; a first process gas inlet unit for introducing a first process gas into a processing space formed between the rotary table and the cylindrical body; an antenna for generating an electric field in the processing space via the window member; and a power source for applying a high frequency voltage to the antenna, the first process gas being converted into plasma to generate an inductively coupled plasma in the processing space, thereby chemically reacting the film; the workpiece is transported through the film forming processing unit, the film processing unit, and the ion irradiation unit; the workpiece is transported through the film forming processing unit, the film processing unit, and the ion irradiation unit; and the workpiece is transported through the film forming processing unit, the film processing unit, and the ion irradiation unit. The workpiece is transported through the film forming processing unit, the film processing unit, and the ion irradiation unit. The workpiece is transported through the film forming processing unit, the film processing unit, and the ion irradiation unit. The ion irradiation unit irradiates the film on the workpiece with ions to planarize the film .

According to the present invention, a film forming apparatus can be obtained that can form a flat film while suppressing deterioration of optical properties.

1 is a perspective plan view showing a schematic configuration of a film forming apparatus according to an embodiment; 2 is a cross-sectional view taken along line AA of FIG. 1. This is a cross-sectional view taken along line B-B of FIG. 4 is a flowchart of a process performed by a film forming apparatus according to an embodiment. 5A to 5C are schematic diagrams showing a process of processing a workpiece by a film forming apparatus according to an embodiment. 1 shows cross-sectional images of Examples 1 and 2 and Comparative Example 1 taken by a transmission electron microscope (TEM), where (a) is a cross-sectional image of Example 1, (b) is a cross-sectional image of Example 2, and (c) is a cross-sectional image of Comparative Example 1. 7 is an enlarged cross-sectional image of the eight surface layers of Examples 1 and 2 and Comparative Example 1 in FIG. 6, where (a) is a cross-sectional image of Example 1, (b) is a cross-sectional image of Example 2, and (c) is a cross-sectional image of Comparative Example 1. 1 is a graph showing the maximum height Rz of each layer in Examples 1 and 2 and Comparative Example 1. 1 is a graph showing the standard deviation of the maximum height Rz of each layer in Examples 1 and 2 and Comparative Example 1.

(Embodiment)
(composition)
An embodiment of a film forming apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective plan view showing a schematic configuration of a film forming apparatus 100 according to this embodiment. This film forming apparatus 100 is an apparatus for forming a film on a workpiece 10. The workpiece 10 is a glass substrate or a resin substrate. The film formed on the workpiece 10 by the film forming apparatus 100 is a laminated film in which a plurality of films are laminated. In this embodiment, the film is a laminated film that becomes an optical film, and is formed by alternately laminating, for example, SiO ₂ films and Nb ₂ O ₅ films.

The film forming apparatus 100 includes a chamber 20, a transport unit 30, a film forming processing unit 40, a film processing unit 50, an ion irradiation unit 60, a load lock unit 70, and a control unit 80.

(Chamber)
The chamber 20 is a cylindrical container that can be evacuated. The inside of the chamber 20 is partitioned by partitions 22 and divided into a plurality of sectors in a fan shape. In each sector, one of the film forming processing section 40, the film processing section 50, the ion irradiation section 60, and the load lock section 70 is disposed. The sections 40, 50, 60, and 70 are disposed in the order of the film forming processing section 40, the film processing section 50, the ion irradiation section 60, and the load lock section 70 with respect to the transport direction (counterclockwise direction in FIG. 1) of the transport section 30. The film processing section 50 and the ion irradiation section 60 are disposed adjacent to each other.

As shown in FIG. 2, the chamber 20 is formed by being surrounded by a disk-shaped ceiling 20a, a disk-shaped inner bottom surface 20b, and an annular inner peripheral surface 20c. The partition 22 is a square wall plate arranged radially from the center of the cylindrical shape, and extends from the ceiling 20a toward the inner bottom surface 20b, but does not reach the inner bottom surface 20b. That is, a cylindrical space is secured on the inner bottom surface 20b side. A rotating table 31 for transporting the workpiece 10 is arranged in this cylindrical space. The lower end of the partition 22 faces the mounting surface of the workpiece 10 on the rotating table 31, with a gap through which the workpiece 10 placed on the transport unit 30 passes. This partition 22 divides the processing space in which the workpiece 10 is processed in the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60. This makes it possible to prevent the sputtering gas G1 in the film forming processing section 40, the process gas (first process gas) G2 in the film processing section 50, and the process gas (second process gas) G3 in the ion irradiation section 60 (see Figure 3) from diffusing within the chamber 20.

As described below, plasma is generated in the processing space in the film forming processing section 40, the film processing section 50, and the ion irradiation section 60, but since it is only necessary to adjust the pressure in the processing space partitioned into a space smaller than the chamber 20, pressure adjustment can be easily performed and plasma discharge can be stabilized. The chamber 20 is provided with an exhaust port 21. An exhaust section 90 is connected to the exhaust port 21. The exhaust section 90 has piping and a pump, valve, etc. (not shown). By exhausting the gas by the exhaust section 90 through the exhaust port 21, the pressure inside the chamber 20 can be reduced to create a vacuum.

(Transportation section)
The transport unit 30 has a rotating table 31, a motor 32, and a holding unit 33, and circulates and transports the workpiece 10 along a transport path L, which is a circumferential trajectory. That is, the transport unit 30 circulates and transports the workpiece 10 so that the workpiece 10 passes through the film forming unit 40, the film processing unit 50, and the ion irradiation unit 60 in that order. Therefore, the transport unit 30 transports the workpiece 10 so that the workpiece 10 passes through the film forming unit 40 and the ion irradiation unit 60 alternately.

The rotating table 31 has a disk shape and is expanded so as not to come into contact with the inner peripheral surface 20c. The motor 32 rotates the rotating table 31 continuously at a predetermined rotation speed with the center of the circle as the rotation axis. In this embodiment, the motor 32 rotates the rotating table 31 counterclockwise as shown in FIG. 1. The holding unit 33 is a groove, hole, protrusion, jig, holder, etc. arranged at equal circumferential positions on the upper surface of the rotating table 31, and holds the tray 34 on which the workpiece 10 is placed by a mechanical chuck or an adhesive chuck. The workpiece 10 is arranged, for example, in a matrix on the tray 34, and six holding units 33 are arranged on the rotating table 31 at 60° intervals.

(Film forming section)
The film forming processing unit 40 generates plasma and exposes a target 42 made of a film forming material to the plasma. In this manner, the film forming processing unit 40 deposits particles constituting the target 42, which are knocked out by colliding ions contained in the plasma with the target 42, on the workpiece 10, thereby forming a film. As shown in FIG. 2, the film forming processing unit 40 includes a sputtering source composed of the target 42, a backing plate 43, and an electrode 44, and a plasma generator composed of a power supply unit 46 and a sputtering gas introduction unit 49.

The target 42 is a plate-shaped member made of a film-forming material that is deposited on the workpiece 10 to form a film. The target 42 serves as a supply source of particles that make up the film to be formed on the workpiece 10. The target 42 is provided at a distance on the transport path L of the workpiece 10 placed on the rotating table 31. The surface of the target 42 is held on the ceiling 20a of the chamber 20 so as to face the workpiece 10 placed on the rotating table 31. For example, three targets 42 are installed. The three targets 42 are provided at positions aligned on the vertices of a triangle in a plan view.

The backing plate 43 is a support member that holds the targets 42. This backing plate 43 holds each target 42 individually. The electrode 44 is a conductive member for applying power to each target 42 individually from outside the chamber 20, and is electrically connected to the targets 42. The power applied to each target 42 can be changed individually. In addition, the sputtering source is appropriately equipped with magnets, cooling mechanisms, etc. as necessary.

The power supply unit 46 is, for example, a DC power supply that applies a high voltage, and is electrically connected to the electrode 44. The power supply unit 46 applies power to the target 42 through the electrode 44. The rotating table 31 is at the same potential as the grounded chamber 20, and a potential difference occurs when a high voltage is applied to the target 42 side. The power supply unit 46 can also be an RF power supply to perform high-frequency sputtering.

2, the sputtering gas introduction unit 49 introduces the sputtering gas G1 into the chamber 20. The sputtering gas introduction unit 49 has a supply source of the sputtering gas G1 such as a cylinder (not shown), a pipe 48, and a gas introduction port 47.

The pipe 48 is connected to a source of sputtering gas G1, hermetically penetrates the chamber 20, and extends into the interior of the chamber 20, with its end opening as a gas inlet 47.

The gas inlet 47 opens between the rotating table 31 and the target 42, and introduces a sputtering gas G1 for film formation into the processing space 41 formed between the rotating table 31 and the target 42. An inert gas can be used as the sputtering gas G1, and argon gas or the like is preferable.

In such a film forming processing section 40, when the sputtering gas G1 is introduced from the sputtering gas introduction section 49 and the power supply section 46 applies a high voltage to the target 42 through the electrode 44, the sputtering gas G1 introduced into the processing space 41 formed between the rotating table 31 and the target 42 becomes plasma, and active species such as ions are generated. The ions in the plasma collide with the target 42 and knock out particles that constitute the target 42 (hereinafter also referred to as target constituent particles). In addition, the workpiece 10, which is circulated and transported by the rotating table 31, passes through this processing space 41. The knocked out target constituent particles are deposited on the workpiece 10 as the workpiece 10 passes through the processing space 41, and a film made of the target constituent particles is formed on the workpiece 10. The workpiece 10 is circulated and transported by the rotating table 31, and the film forming process is performed by repeatedly passing through this processing space 41. The thickness of the film deposited each time it passes through the film forming processing section 40 depends on the processing rate of the film processing section 50, but it is preferable that it is a thin film of, for example, about 1 to 2 atoms (5 nm or less). By circulating and transporting the workpiece 10 multiple times, the thickness of the film increases, and a film with a predetermined thickness is formed on the workpiece 10 .

The pressure of the sputtering gas in the film forming processing unit 40 can be set to 0.3 Pa or less, and the pressure can be lowered below 0.3 Pa as long as the plasma generated in the processing space 41 of the film forming processing unit 40 can be maintained.

In this embodiment, the film forming apparatus 100 includes a plurality of (here, two) film forming processing units 40, which are provided in two compartments separated by a partition 22. The plurality of film forming processing units 40 selectively deposit the film forming materials to form a film consisting of layers of a plurality of film forming materials. In particular, in this embodiment, sputtering sources corresponding to different types of film forming materials are included, and a film consisting of layers of a plurality of types of film forming materials is formed by selectively depositing the film forming materials. Including sputtering sources corresponding to different types of film forming materials includes cases in which the film forming materials of all the film forming processing units 40 are different, and cases in which the film forming materials are common to the plurality of film forming processing units 40 but different from the others. Selectively depositing the film forming materials one by one means that while a film forming processing unit 40 of one type of film forming material forms a film, the film forming processing units 40 of the other film forming materials do not form a film.

In this embodiment, the target 42 of one film forming processing unit 40 is made of silicon (Si), and the target 42 of the other film forming processing unit 40 is made of niobium (Nb). While a silicon film is being formed, a niobium film is not formed, and while a niobium film is being formed, a silicon film is not formed. To distinguish between the two film forming processing units 40, the film forming processing unit 40 having a target 42 made of silicon (Si) is referred to as film forming processing unit 40a, and the film forming processing unit 40 having a target 42 made of niobium (Nb) is referred to as film forming processing unit 40b.

(Membrane processing section)
The film processing section 50 generates an inductively coupled plasma in the processing space 59 into which the process gas is introduced, and generates a compound film by chemically reacting ions in the plasma with the film formed on the workpiece 10 by the film forming processing section 40. The process gas introduced includes, for example, oxygen or nitrogen. The process gas may include an inert gas such as argon gas in addition to oxygen gas or nitrogen gas. When the process gas includes oxygen, the film processing section 50 oxidizes the film on the workpiece 10. When the process gas includes nitrogen, the film processing section 50 nitrides the film on the workpiece 10. The process gas in this embodiment is oxygen. The film processing section 50 turns oxygen gas into plasma, and chemically reacts ions in the plasma with a silicon film or a niobium film on the outermost surface of the workpiece 10 to generate a SiO ₂ film or a Nb ₂ O ₅ film.

The film processing section 50 has a plasma generator consisting of a cylindrical body 51, a window member 52, an antenna 53, an RF power supply 54, a matching box 55 and a process gas inlet section 58.

As shown in Figs. 1 and 2, the cylindrical body 51 is a cylinder with a rounded rectangular cross section and has an opening. The cylindrical body 51 is fitted into the ceiling 20a of the chamber 20 so that the opening faces the turntable 31 side and protrudes into the internal space of the chamber 20. The cylindrical body 51 is made of the same material as the turntable 31. The window member 52 is a flat plate of a dielectric material such as quartz having a shape similar to the horizontal cross section of the cylindrical body 51. The window member 52 is provided to close the opening of the cylindrical body 51 and separates the processing space 59 into which the process gas G2 containing oxygen gas in the chamber 20 is introduced from the inside of the cylindrical body 51. The processing space 59 is a space formed between the turntable 31 and the inside of the cylindrical body 51 in the film processing section 50. The workpiece 10 circulated and transported by the turntable 31 repeatedly passes through this processing space 59 to perform the oxidation process. The window member 52 may be a dielectric material such as alumina, or a semiconductor such as silicon.

The antenna 53 is a conductor wound into a coil shape, and is disposed in the internal space of the cylindrical body 51, which is isolated from the processing space 59 in the chamber 20 by the window member 52, and generates an electric field by passing an alternating current through it. It is desirable to dispose the antenna 53 near the window member 52 so that the electric field generated by the antenna 53 is efficiently introduced into the processing space 59 through the window member 52. An RF power supply 54 that applies a high frequency voltage is connected to the antenna 53. A matching box 55, which is a matching circuit, is connected in series to the output side of the RF power supply 54. The matching box 55 stabilizes the plasma discharge by matching the impedance on the input side and the output side.

2, the process gas introduction unit 58 introduces a process gas G2 containing oxygen gas into the processing space 59. The process gas introduction unit 58 has a supply source of the process gas G2 such as a cylinder (not shown), a pipe 57, and a gas introduction port 56.

The pipe 57 is connected to a source of process gas G2, hermetically penetrates the chamber 20, and extends into the interior of the chamber 20, with its end opening as a gas inlet 56.

The gas inlet 56 opens into the processing space 59 between the window member 52 and the rotating table 31 and introduces process gas G2.

In such a film processing section 50, a high-frequency voltage is applied to the antenna 53 from the RF power supply 54. This causes a high-frequency current to flow through the antenna 53, generating an electric field due to electromagnetic induction. The electric field is generated in the processing space 59 through the window member 52, generating an inductively coupled plasma of the process gas G2. At this time, the oxygen gas is also ionized, and the oxygen ions collide with the film on the workpiece 10 and bond with the atoms that make up the film. As a result, the film on the workpiece 10 is oxidized, and an oxide film is formed as a compound film.

(Ion irradiation unit)
The ion irradiation unit 60 irradiates the target with ions. The ion irradiation unit 60 converts the process gas into plasma and irradiates the target with ions contained in the plasma. The target is a film in the process of being formed on the workpiece 10. The film in the process of being formed on the workpiece 10 is a film until it reaches a film of a desired thickness to be formed on the workpiece 10, specifically, a compound film on the workpiece 10 that has been processed by the film processing unit 50, or a film on the workpiece 10 that has been formed by the film forming processing unit 40. In other words, the transport unit 30 circulates and transports the workpiece 10 so that the workpiece 10 passes through the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60, and the ion irradiation unit 60 irradiates the compound film on the workpiece 10 that has been processed by the film processing unit 50 with ions. Alternatively, in the direction of transport by the transport unit 30 of each unit 40, 50, 60, when the film formation processing unit 40, the ion irradiation unit 60, and the film processing unit 50 are arranged in this order, the transport unit 30 circulates and transports the workpiece 10 so that the workpiece 10 passes through the film formation processing unit 40, the ion irradiation unit 60, and the film processing unit 50, whereby the ion irradiation unit 60 irradiates ions onto the film on the workpiece 10 formed by the film formation processing unit 40. The ion irradiation unit 60 includes a plasma generator composed of a cylindrical electrode 61, a shield 64, an RF power source 66, and a process gas introduction unit 65.

3, the ion irradiation section 60 is provided with a cylindrical electrode 61 provided from the top to the inside of the chamber 20. The cylindrical electrode 61 is a square tube with an opening 61a at one end and a closed other end. The cylindrical electrode 61 is attached to an opening 21a provided in the ceiling of the chamber 20 via an insulating member 62 so that the end having the opening 61a faces the rotating table 31. The sidewall of the cylindrical electrode 61 extends into the interior of the chamber 20.

An outwardly extending flange 61b is provided at the end of the cylindrical electrode 61 opposite the opening 61a. An insulating member 62 is fixed between the flange 61b and the periphery of the opening 21a of the chamber 20, thereby keeping the interior of the chamber 20 airtight. The insulating member 62 need only be insulating and is not limited to a specific material, but can be made of, for example, a material such as PTFE (polytetrafluoroethylene).

The opening 61a of the cylindrical electrode 61 is disposed at a position facing the conveying path L of the rotating table 31. The rotating table 31, which serves as the conveying section 30, conveys the tray 34 carrying the workpiece 10 and passes through a position facing the opening 61a. Note that the opening 61a of the cylindrical electrode 61 is larger than the size of the tray 34 in the radial direction of the rotating table 31.

1, the cylindrical electrode 61 is in the shape of a fan expanding from the center side to the outside in the radial direction of the rotating table 31 when viewed from the planar direction. The fan shape here means the shape of the fan surface of a folding fan. The opening 61a of the cylindrical electrode 61 is also in the shape of a fan. The speed at which the tray 34 on the rotating table 31 passes the position facing the opening 61a becomes slower toward the center in the radial direction of the rotating table 31 and becomes faster toward the outside. Therefore, if the opening 61a is simply rectangular or square, there will be a difference in the time it takes for the workpiece 10 to pass the position facing the opening 61a between the center side and the outside in the radial direction. By expanding the diameter of the opening 61a from the center side to the outside in the radial direction, the time it takes to pass the opening 61a can be made constant, and the plasma processing described below can be made uniform. However, as long as the difference in the passing time does not cause any problems in the product, the opening 61a may be rectangular or square.

As described above, the cylindrical electrode 61 passes through the opening 21a of the chamber 20, and a portion of it is exposed to the outside of the chamber 20. The portion of the cylindrical electrode 61 exposed to the outside of the chamber 20 is covered by a housing 63, as shown in FIG. 3. The housing 63 keeps the space inside the chamber 20 airtight. The portion of the cylindrical electrode 61 located inside the chamber 20, i.e., the periphery of the side wall, is covered by a shield 64.

The shield 64 is a sector-shaped rectangular tube coaxial with the cylindrical electrode 61 and is larger than the cylindrical electrode 61. The shield 64 is connected to the chamber 20. Specifically, the shield 64 stands upright from the edge of the opening 21a of the chamber 20, and the end extending toward the inside of the chamber 20 is located at the same height as the opening 61a of the cylindrical electrode 61. The shield 64 acts as a cathode like the chamber 20, so it is preferable to make it out of a conductive metal material with low electrical resistance. The shield 64 may be molded integrally with the chamber 20, or may be attached to the chamber 20 using a fixing bracket or the like.

The shield 64 is provided to stably generate plasma in the cylindrical electrode 61. Each side wall of the shield 64 is provided to extend approximately parallel to each side wall of the cylindrical electrode 61 with a predetermined gap therebetween. If the gap is too large, the capacitance will be small and the plasma generated in the cylindrical electrode 61 will enter the gap, so it is desirable that the gap be as small as possible. However, if the gap is too small, the capacitance between the cylindrical electrode 61 and the shield 64 will be large, which is not preferable. The size of the gap should be set appropriately according to the capacitance required to generate plasma. Note that FIG. 3 only shows two side wall surfaces extending in the radial direction of the shield 64 and the cylindrical electrode 61, but a gap of the same size as the radial side wall surfaces is provided between the two side wall surfaces extending in the circumferential direction of the shield 64 and the cylindrical electrode 61.

A process gas inlet 65 is connected to the cylindrical electrode 61. In addition to piping, the process gas inlet 65 has a gas supply source for process gas G3, a pump, a valve, etc. (not shown). The process gas G3 is introduced into the cylindrical electrode 61 by the process gas inlet 65. The process gas G3 can be changed as appropriate depending on the purpose of the process. For example, the process gas G3 may contain argon gas, oxygen gas, or nitrogen gas, or may contain oxygen gas or nitrogen gas in addition to argon gas.

An RF power supply 66 for applying a high frequency voltage is connected to the cylindrical electrode 61. A matching box 67, which is a matching circuit, is connected in series to the output side of the RF power supply 66. The RF power supply 66 is also connected to the chamber 20. When a voltage is applied from the RF power supply 66, the cylindrical electrode 61 acts as an anode, and the chamber 20, the shield 64, the rotating table 31, and the tray 34 act as cathodes. In other words, they function as electrodes for reverse sputtering. For this reason, as described above, the rotating table 31 and the tray 34 are conductive and are in contact so as to be electrically connected.

The matching box 67 stabilizes the plasma discharge by matching the impedance of the input side and the output side. The chamber 20 and the rotating table 31 are grounded. The shield 64 connected to the chamber 20 is also grounded. The RF power supply 66 and the process gas inlet 65 are both connected to the cylindrical electrode 61 via a through hole provided in the housing 63.

Argon gas, which is the process gas G3, is introduced into the cylindrical electrode 61 from the process gas inlet 65, and when a high-frequency voltage is applied to the cylindrical electrode 61 from the RF power source 66, a capacitively coupled plasma is generated, the argon gas is converted into plasma, and electrons, ions, radicals, etc. are generated. The ions in this generated plasma are irradiated onto the film being formed on the workpiece 10.

That is, the ion irradiation unit 60 has a cylindrical electrode 61 with an opening 61a at one end and into which a process gas G3 is introduced, and an RF power source 66 that applies a high-frequency voltage to the cylindrical electrode 61, and the transport unit 30 transports the workpiece 10 directly below the opening 61a and passes it through, thereby attracting ions into the film formed on the workpiece 10 and irradiating the ions. In the ion irradiation unit 60, a negative bias voltage is applied to the tray 34 on which the workpiece 10 is placed and the rotating table 31 in order to attract ions into the film formed on the workpiece 10.

By using a cylindrical electrode 61 such as the ion irradiation unit 60, it is possible to attract ions into the formed thin film by applying a desired negative bias voltage to the tray 34 and turntable 31 on which the workpiece 10 is placed, without applying a high-frequency voltage to the tray 34 or turntable 31, while these components remain at earth potential. This makes it possible to add a structure for applying a high-frequency voltage to the tray 34 or turntable 31, or to consider the area ratio of the anode electrode to the area of other components surrounding the cathode electrode in order to obtain the desired bias voltage, making the device design easier.

Therefore, even when film formation and ion irradiation are repeated while moving the workpiece 10 in order to flatten a film in the process of being formed on the workpiece 10, ions can be attracted to the film formed on the workpiece 10 with a simple structure.

In this way, the film processing section 50 has the function of generating a compound film by converting oxygen gas or nitrogen gas into plasma to generate ions, which then react chemically with the film formed on the workpiece 10. By utilizing inductively coupled plasma with a high plasma density, the film processing section 50 is able to generate a compound film by efficiently chemically reacting the ions in the plasma with the film formed on the workpiece 10 by the film forming section 40.

The ion irradiation unit 60 applies a negative bias voltage to the tray 34 on which the workpiece 10 is placed and the rotating table 31, and has the function of attracting ions into the film formed on the workpiece 10 and flattening the thin film. The ion irradiation unit 60 uses a cylindrical electrode 61 to easily attract ions into the film formed on the workpiece 10 and flatten it.

(Load lock section)
The load lock unit 70 is a device that, while maintaining the vacuum of the chamber 20, carries the tray 34 carrying the unprocessed workpieces 10 from the outside into the chamber 20 by a transport means not shown, and discharges the tray 34 carrying the processed workpieces 10 to the outside of the chamber 20. Since a known structure can be applied to this load lock unit 70, a description thereof will be omitted.

(Control device)
The control device 80 controls various elements constituting the film forming apparatus 100, such as the exhaust unit 90, the sputtering gas introduction unit 49, the process gas introduction units 58 and 65, the power supply unit 46, the RF power supplies 54 and 66, and the transport unit 30. The control device 80 is a processing device including a PLC (Programmable Logic Controller) and a CPU (Central Processing Unit), and stores a program describing the control contents. Specific controlled contents include the initial exhaust pressure of the film forming apparatus 100, the power applied to the target 42 and the antenna 53, the flow rates of the sputtering gas G1 and the process gases G2 and G3, the introduction time and exhaust time, the film forming time, and the rotation speed of the motor 32. The control device 80 can be adapted to a wide variety of film forming specifications.

(motion)
Next, the overall operation of the film forming apparatus 100 controlled by the control device 80 will be described. FIG. 4 is a flowchart of the process by the film forming apparatus 100 according to this embodiment. First, the trays 34 carrying the workpieces 10 are sequentially carried into the chamber 20 from the load lock unit 70 by the transport means (step S01). In step S01, the turntable 31 moves the empty holders 33 sequentially to the carry-in location from the load lock unit 70. The holders 33 individually hold the trays 34 carried in by the transport means. In this way, all the trays 34 carrying the workpieces 10 to be filmed are placed on the turntable 31.

The chamber 20 is constantly depressurized by exhausting air from the exhaust port 21 by the exhaust unit 90. The chamber 20 is depressurized to a predetermined pressure (step S02). Then, the rotating table 31 carrying the workpiece 10 rotates and reaches a predetermined rotation speed (step S03).

When the rotation of the rotating table 31 reaches a predetermined rotation speed, the film forming processing unit 40a starts to operate and forms a silicon film on the workpiece 10 (step S04). That is, the sputtering gas inlet 49 supplies sputtering gas G1 through the gas inlet 47. The sputtering gas G1 is supplied to the periphery of the target 42 made of a silicon material. The power supply unit 46 applies a voltage to the target 42. This converts the sputtering gas G1 into plasma. Ions generated by the plasma collide with the target 42 and knock out silicon particles. Silicon particles are deposited on the surface of the workpiece 10 passing through the film forming processing unit 40a each time it passes, forming a silicon film.

The workpiece 10, which has passed through the film forming processing section 40a by the rotation of the rotary table 31 and has a silicon film formed thereon, heads toward the film processing section 50, where the silicon film is oxidized (step S05). That is, the process gas inlet 58 supplies a process gas G2 containing oxygen gas through the gas inlet 56. The process gas G2 containing oxygen gas is supplied to a processing space 59 sandwiched between the window member 52 and the rotary table 31. The RF power supply 54 applies a high-frequency voltage to the antenna 53. An electric field generated by the antenna 53, in which a high-frequency current flows due to the application of the high-frequency voltage, is generated in the processing space 59 through the window member 52, and excites the process gas G2 containing oxygen gas supplied to this space to generate plasma. Furthermore, oxygen ions generated by the plasma collide with the silicon film formed on the workpiece 10, and are bonded to silicon, and the silicon film on the workpiece 10 is converted into a SiO ₂ film.

The workpiece 10, which has passed through the film processing section 50 by the rotation of the turntable 31 and has a SiO ₂ film formed thereon, heads toward the ion irradiation section 60, where ions are irradiated onto the SiO ₂ film (step S06). That is, the process gas introduction section 65 supplies a process gas G3 containing argon gas through a pipe. This process gas G3 is supplied to the space inside the cylindrical electrode 61 surrounded by the cylindrical electrode 61 and the turntable 31. When a voltage is applied to the cylindrical electrode 61 by the RF power supply 66, the cylindrical electrode 61 acts as an anode, and the chamber 20, the shield 64, the turntable 31, and the tray 34 act as cathodes, exciting the process gas G3 supplied to the space inside the cylindrical electrode 61 to generate plasma. Furthermore, the argon ions generated by the plasma collide with the SiO ₂ film formed on the workpiece 10, thereby moving particles to the sparse portion of the film and flattening the film surface.

Thus, in steps S04 to S06, the workpiece 10 passes through the processing space 41 of the film-forming processing unit 40a in operation to perform the film-forming processing, and the workpiece 10 passes through the processing space 59 of the film-forming processing unit 50 in operation to perform the oxidation processing. Then, the SiO ₂ film formed on the workpiece 10 is planarized by the workpiece 10 passing through the space in the cylindrical electrode 61 of the ion irradiation unit 60 in operation. Note that "operating" is synonymous with a plasma generating operation that generates plasma in the processing space of each unit 40a, 50, 60.

The operation of the film processing unit 50 may be started before the workpiece 10 on which the first film has been formed in the film forming unit 40a reaches the film processing unit 50. The operation of the ion irradiation unit 60 may be started before the workpiece 10 on which the oxidation process has been performed in the film processing unit 50 reaches the ion irradiation unit 60.

The rotating table 31 continues to rotate until a SiO ₂ film of a predetermined thickness is formed on the workpiece 10, that is, until a predetermined time obtained in advance by simulation, experiment, etc. has elapsed (NO in step S07). In other words, until a SiO ₂ film of a predetermined thickness is formed, the workpiece 10 continues to circulate by the transport unit 30 through the film forming unit 40a, the film processing unit 50, and the ion irradiation unit 60 in sequence, and the film forming process (step S04) for depositing silicon particles on the workpiece 10, the oxidation process (step S05) for oxidizing the deposited silicon particles, and the planarization process (step S06) for planarizing the generated SiO ₂ film by ion irradiation are sequentially repeated.

After a predetermined time has elapsed (YES in step S07), the operation of the film forming processing unit 40a is stopped (step S08). Specifically, the introduction of the sputtering gas G1 by the sputtering gas introduction unit 49 is stopped, and the application of voltage to the target 42 by the power supply unit 46 is stopped. When the film forming processing unit 40a is stopped, the operation of the film processing unit 50 and the ion irradiation unit 60 may also be stopped, and the operation may be resumed until the work 10 on which the first film has been formed in the film forming processing unit 40b, where the next film is formed, reaches the film processing unit 50 and the ion irradiation unit 60. In addition, even if the operation of the film forming processing unit 40a is stopped, the operation of the film processing unit 50 and the ion irradiation unit 60 may not be stopped. In this case, the film processing unit 50 and the ion irradiation unit 60 will be operating until the operation of the film forming processing unit 40a and the film forming processing unit 40b is stopped.

Next, the film forming processing unit 40b starts to operate, and a niobium film is formed on the planarized SiO ₂ film (step S09). That is, the sputtering gas inlet 49 supplies the sputtering gas G1 through the gas inlet 47. The sputtering gas G1 is supplied to the periphery of the target 42 made of a niobium material. The power supply unit 46 applies a voltage to the target 42. This causes the sputtering gas G1 to become plasma. Ions generated by the plasma collide with the target 42 and knock out niobium particles. Niobium particles are deposited on the surface of the workpiece 10 passing through the film forming processing unit 40b each time the workpiece 10 passes through the film forming processing unit 40b, and a niobium film is formed.

The workpiece 10, which has passed through the film forming processing section 40b by the rotation of the turntable 31 and has the niobium film formed thereon, heads toward the film processing section 50, where the niobium film is oxidized (step S10). That is, similar to step S05, the process gas G2 containing oxygen gas is supplied to the processing space 59 by the process gas introduction section 58, and a high frequency voltage is applied to the antenna 53 by the RF power supply 54, thereby generating plasma in the processing space 59. Oxygen ions generated by this plasma collide with the niobium film formed on the workpiece 10, and are bonded to the niobium, so that the niobium film on the workpiece 10 is converted into an Nb ₂ O ₅ film.

The workpiece 10, which has passed through the film processing section 50 by the rotation of the turntable 31 and has the Nb ₂ O ₅ film formed thereon, moves toward the ion irradiation section 60, where the Nb ₂ O ₅ film is irradiated with ions (step S11). That is, similar to step S06, the process gas G3 containing argon gas is supplied from the process gas introduction section 65 to the processing space surrounded by the cylindrical electrode 61 and the turntable 31, and the RF power supply 66 applies a voltage to the cylindrical electrode 61, thereby exciting the process gas G3 supplied to the processing space to generate plasma. Furthermore, the argon ions generated by the plasma collide with the Nb ₂ O ₅ film formed on the workpiece 10, thereby moving particles to the sparse portion of the film and flattening the film surface.

The rotating table 31 continues to rotate until a Nb ₂ O ₅ film of a predetermined thickness is formed on the workpiece 10, that is, until a predetermined time obtained in advance by simulation, experiment, etc. has elapsed (NO in step S12). In other words, until a Nb ₂ O ₅ film of a predetermined thickness is formed, the workpiece 10 continues to circulate by the conveying unit 30 through the film forming unit 40b, the film processing unit 50, and the ion irradiation unit 60 in sequence, and a film forming process (step S09) for depositing niobium particles on the workpiece 10, an oxidation process (step S10) for oxidizing the deposited niobium particles, and a flattening process (step S11) for flattening the generated Nb ₂ O ₅ film by ion irradiation are sequentially repeated.

After the predetermined time has elapsed (YES in step S12), the operation of the film forming processing unit 40b is stopped (step S13). Specifically, the introduction of the sputtering gas G1 by the sputtering gas introduction unit 49 is stopped, and the application of voltage to the target 42 by the power supply unit 46 is stopped.

In this manner, the SiO ₂ films 11 and the Nb ₂ O ₅ films 12 are alternately laminated on the workpiece 10, for example as shown in FIG. 5, by repeating steps S04 to S13 until a predetermined number of each film is formed.

After a predetermined number of _SiO2 films and _{Nb2O5 films} are formed, the film forming unit 40, the film processing unit 50, and the ion irradiation unit 60 are stopped (step S15). That is, the introduction of the sputtering gas G1, the introduction of the process gases G2 and G3, and the voltage application by the power supply unit 46 and the RF power supplies 54 and 66 are stopped. Then, the rotation of the turntable 31 is stopped, and the tray 34 on which the workpiece 10 is placed is removed from the load lock unit 70 (step S16).

(Action)
As described above, in the film forming apparatus 100, the conveying unit 30 circulates and transports the workpiece 10 so that the workpiece 10 passes through the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60. Therefore, until the _SiO2 film and _{the Nb2O5 film} each reach a predetermined thickness, the ion irradiation unit 60 irradiates ions onto the film in the process of being formed, thereby reducing the unevenness of the film, and a flat film can be laminated.

That is, in the formation of a laminated film in which multiple films are stacked, the particles in the film are sparsely distributed and densely distributed, resulting in unevenness in the film. In this embodiment, however, the ion irradiation unit 60 irradiates the uneven film with ions during the film formation, thereby moving the particles to the sparsely distributed parts of the film and flattening the film, so that a flat and dense film with no or few unevenness can be formed. Furthermore, in the case of forming another type of film on the film, the ion irradiation unit 60 irradiates the uneven film with ions during the film formation, thereby moving the particles to the sparsely distributed parts of the film and flattening the film, so that a flat and dense film with no or few unevenness can be formed.

(effect)
(1) The film formation apparatus 100 of this embodiment is a film formation apparatus that forms a film on a workpiece 10, and includes a transport unit 30 having a rotary table 31 that circulates and transports the workpiece 10, a target 42 made of a material that constitutes the film, and a plasma generator that converts a sputtering gas introduced between the target 42 and the rotary table 31 into plasma. The film formation processing unit 40 sputters the target 42 with the plasma to form a film on the workpiece 10, and an ion irradiation unit 60 that irradiates ions. The transport unit 30 transports the workpiece 10 so that it passes through the film formation processing unit 40 and the ion irradiation unit 60 in the middle of forming the film, and the ion irradiation unit 60 irradiates ions onto the film that is in the middle of being formed on the workpiece 10.

This allows a flat film to be formed. That is, when the film is formed by the film forming processing unit 40 using the sputtering technique, particles knocked out from the target 42 tend to accumulate at specific locations on the workpiece 10, and the formed film is prone to unevenness. In contrast, by irradiating ions onto the film being formed on the workpiece 10 by the ion irradiation unit 60, the ions collide with the protruding parts of the film, causing them to collapse, and the collapsed parts fit into the surrounding recesses, thereby flattening the film. Then, a film is further formed on the flattened film by the film forming processing unit 40, and the film is flattened by ion irradiation, so that the flatness can be increased compared to the case where a film of a predetermined thickness is formed and then only its surface is flattened.

In order to suppress the unevenness on the surface of the film formed by sputtering, there is a method in which the workpiece is heated while the film formation process is performed, and thermal energy is applied to the sputtered particles on the surface of the workpiece, so that the sputtered particles move to the sparse areas and are flattened. However, in a film formation apparatus in which the workpiece is circulated and transported by rotating the turntable and repeatedly passes directly under the film formation unit that forms the film by sputtering, it is necessary to heat the entire turntable in order to heat the workpiece on the turntable, which requires a large amount of energy and makes the configuration of the film formation apparatus complicated. In contrast, in this embodiment, the transport unit 30 transports the workpiece 10 so that it passes through the film formation processing unit 40 and the ion irradiation unit 60 during the film formation, and the ion irradiation unit 60 irradiates ions to the film on the workpiece 10 during its formation, so that the film can be flattened without heating the workpiece 10, which prevents the device configuration from becoming complicated and saves energy.

In addition, this embodiment is a film formation apparatus 100 for forming a film on a workpiece 10, the apparatus including a chamber 20 capable of evacuating the inside thereof, a transport unit 30 provided within the chamber and having a rotary table 31 for circulating and transporting the workpiece 10 on a circumferential transport path, a target 42 made of a material for forming the film, a plasma generator for converting a sputtering gas G1 introduced between the target 42 and the rotary table 31 into plasma, and a film formation processing unit 40 for sputtering the target 42 with the plasma to form a film on the workpiece 10, a cylindrical body 51 protruding into the internal space of the chamber 20 and opening toward the transport path, a window member 52 provided to close the opening of the cylindrical body, a first process gas introduction unit (process gas introduction unit 58) for introducing a first process gas (process gas G2) into a processing space 59 formed between the rotary table 31 and the cylindrical body 51, and an electric current supply unit (Electric current supply unit) for supplying an electric current to the processing space 59 through the window member 52. The apparatus further comprises a film processing section 50 which converts a first process gas G2 into plasma to generate inductively coupled plasma in a processing space 59 and chemically reacts with a film, a cylindrical electrode 61 which has an opening 61a at one end and is attached to the chamber 20 so that the opening 61a faces the transport path, a second process gas inlet section (process gas inlet section 65) which introduces a second process gas (process gas G3) into the cylindrical electrode 61, and an RF power source 66 which applies a high frequency voltage to the cylindrical electrode 61. The apparatus further comprises an ion irradiation section 60 which irradiates the film with ions generated by converting the second process gas G3 into plasma, and the transport section 30 circulates and transports the workpiece 10 so that the workpiece 10 passes through the film forming section 40, the film processing section 50, and the ion irradiation section 60, and the ion irradiation section 60 irradiates the film being formed on the workpiece 10 with ions.

As a result, the film formed by the film forming processing unit 40 can be chemically reacted by the film processing unit 50 and planarized by the ion irradiation unit 60. The ion irradiation unit 60 has a second process gas inlet for introducing the second process gas G3, a cylindrical electrode 61 having an opening 61a at one end and into which the second process gas G3 is introduced, and a power source (RF power source 66) for applying a high frequency voltage to the cylindrical electrode 61, so that a negative bias voltage can be easily applied even to the workpiece 10 moving by circulatory transport. This makes it possible to attract ions to the workpiece 10, and the film on the workpiece 10 can be efficiently planarized. On the other hand, in the film processing unit 50, the film on the workpiece 10 can be efficiently converted into a compound film by inductively coupled plasma having a higher plasma density than the plasma generated by the ion irradiation unit 60.

In this way, in the film forming apparatus 100 of this embodiment, the film processing unit 50 and the ion irradiation unit 60 are separated as separate components, and the film forming unit 40, the film processing unit 50, and the ion irradiation unit 60 are circulated and transported to pass the workpiece 10, so that film formation with an atomic-level film thickness, conversion to a compound film, and planarization can be repeatedly performed on the workpiece 10. As a result, when forming an optical film that includes an oxide film, for example, it is possible to stack films with high flatness and high oxidation efficiency, and an optical film with high optical properties can be formed.

(2) The conveying unit 30 conveys the workpiece 10 so that it alternately passes through the film forming processing unit 40 and the ion irradiation unit 60. This allows a film to be formed on the planarized film to a predetermined thickness, resulting in a flatter film.

(3) The apparatus includes a process gas inlet section 58 for introducing a process gas G2, a plasma generator for converting the process gas into plasma, and a film processing section 50 for chemically reacting the film formed by the film forming section 40. The transport section 30 transports the workpiece 10 so that it passes through the ion irradiation section 60 after passing through the film processing section 50. This makes it possible to flatten the compound film formed on the workpiece 10.

(4) The process gas G2 contains oxygen or nitrogen. This allows the film deposited on the workpiece 10 to be oxidized or nitrided.

(5) The pressure of the sputtering gas in the film forming processing unit 40 is set to 0.3 Pa or less. This reduces the reduction in kinetic energy of the target constituent particles caused by collisions between the target constituent particles ejected from the target 42 and constituent particles such as atoms and ions in the sputtering gas, so that the target constituent particles reach the workpiece 10 or the film on its surface while retaining a relatively large kinetic energy, and move on the workpiece 10 or the film on its surface. As a result, the target constituent particles are accommodated in the recessed parts of the film, and the film can be made flat.

(6) The film forming apparatus 100 of this embodiment includes a plurality of film forming processing sections 40, which are configured to alternately stack films of different compositions on the workpiece 10. This makes it possible to obtain an optical device having an optical film with good optical properties in which diffuse reflection of light on the film surface is suppressed.

(7) The ion irradiation unit 60 has a process gas introduction unit 65 that introduces a process gas (second process gas) G3, and a plasma generator that converts the process gas G3 into plasma, and ions in the plasma generated by the plasma generator are irradiated onto the film. The process gas G3 also contains argon. This allows argon ions with large atomic size to collide with the film, which is a collection of particles deposited on the workpiece 10, thereby breaking down the convex parts of the film, which are dense particles, and making it easier to fit the broken particles into the concave parts of the film, which are sparse parts, and making it easier to flatten the film.

(8) The process gas (second process gas) G3 contains oxygen or nitrogen, or argon and oxygen or nitrogen. As a result, if the oxidation or nitridation by the membrane processing section 50 is insufficient, the oxygen ions or nitrogen ions react with the membrane in the ion irradiation section 60 to oxidize or nitride, thereby compensating for the reaction. For example, if the work 10 passes through the membrane processing section 50 before the ion irradiation section 60, even if the oxidation or nitridation is insufficient in the membrane processing section 50, the oxygen ions or nitrogen ions react with the membrane in the ion irradiation section 60 that the work 10 passes through next, and the reaction can be compensated for by being oxidized or nitrided. In addition, if the process gas (second process gas) G3 contains argon, the collision of argon ions may cause oxygen atoms and nitrogen atoms to separate from the oxidized or nitrided membrane, resulting in insufficient oxidation or nitridation of the membrane. Even in that case, the reaction can be compensated for by the oxygen ions or nitrogen ions reacting with the membrane again to oxidize or nitride. For example, when the workpiece 10 passes through the film treatment section 50 before the ion irradiation section 60, even if oxidation or nitridation is performed in the film treatment section 50, the oxidized or nitrided oxygen atoms and nitrogen atoms may be separated by the collision of argon ions in the ion irradiation section 60, resulting in insufficient oxidation or nitridation. Even in such a case, the oxygen ions or nitrogen ions may chemically react again with the film in the ion irradiation section 60 to oxidize or nitride, thereby compensating for the reaction.

(Example)
Using the film-forming apparatus 100 of this embodiment, a cold mirror was fabricated by forming _a total of 22 laminated layers of _SiO2 films and _Nb2O5 films alternately on the workpiece 10 under the conditions shown in Table 1. The numerical range of "target applied power (W)" in the "film-forming processing section" in Table 1 indicates the range of power supplied to each of the three targets 42.

The cold mirror of Example 1 was produced by oxidizing the films of each layer by the film processing unit 50 and then irradiating the films with ions by the ion irradiation unit 60. The cold mirror of Example 2 was produced under the same conditions as Example 1, except that the supply flow rate of sputtering gas G1 to the film formation processing unit 40 was reduced to 50 sccm from that of Example 1. In other words, the pressure of the sputtering gas in the film formation processing unit 40 was 0.5 Pa in Example 1 and 0.3 Pa in Example 2. The cold mirror of Comparative Example 1 was produced without ion irradiation by the ion irradiation unit 60, as compared to Example 1.

The entire cross section and the eight outer layers of Examples 1 and 2 and Comparative Example 1 were photographed using a Hitachi High-Technologies Corporation H-9500 transmission electron microscope (TEM) at an acceleration voltage of 200 kV to obtain cross-sectional images.

Figure 6 shows cross-sectional images of Examples 1 and 2 and Comparative Example 1 taken by a transmission electron microscope (TEM), where (a) is a cross-sectional image of Example 1, (b) is a cross-sectional image of Example 2, and (c) is a cross-sectional image of Comparative Example 1. Figure 7 shows enlarged cross-sectional images of the eight surface layers of Examples 1 and 2 and Comparative Example 1 in Figure 6, where (a) is a cross-sectional image of Example 1, (b) is a cross-sectional image of Example 2, and (c) is a cross-sectional image of Comparative Example 1.

Figure 8 is a graph showing the maximum height Rz of each layer in Examples 1 and 2 and Comparative Example 1. Figure 9 is a graph showing the standard deviation of the maximum height Rz of each layer in Examples 1 and 2 and Comparative Example 1. The "maximum height" in Figures 8 and 9 refers to the height of the protruding part closest to the surface of the workpiece 10, based on the part of each layer closest to the workpiece 10.

As shown in Figures 6(a) and 7(a) and Figures 6(c) and 7(c), it can be seen that the film of each layer in Example 1 is flatter than that in Comparative Example 1. Also, as shown in Figures 8 and 9, the average maximum height Rz of each layer in Example 1 is 38% smaller than that in Comparative Example 1, and the average standard deviation of each layer is 40% smaller, so it can be seen that the film of each layer is flatter. Thus, the difference between Example 1 and Comparative Example 1 is the difference in the presence or absence of ion irradiation on the film, so that the effect of flattening the film by ion irradiation can be confirmed both visually and numerically as shown in Figures 6 to 9.

As shown in Figs. 6(a) and 7(a) and Figs. 6(b) and 7(b), it can be seen that the film of each layer in Example 2 is even flatter than that in Example 1. As shown in Figs. 8 and 9, the average maximum height Rz of each layer in Example 2 is 56% smaller than that in Example 1, and the average standard deviation of each layer is 63% smaller, so it can be seen that the film of each layer is even flatter. Thus, the difference between Example 2 and Example 1 is the difference in the flow rate of the sputtering gas supplied to the film forming processing unit 40, that is, the difference in the pressure of the sputtering gas. Therefore, as shown in Figs. 6 to 9, the effect of further flattening the film by lowering the pressure of the film forming atmosphere can be confirmed both visually and numerically.

Note that Examples 1 and 2 and Comparative Example 1 have a laminated film having 22 layers. Looking at the maximum height Rz and standard deviation of the first layer in Figures 8 and 9, it can be seen that Examples 1 and 2 have smaller maximum height Rz and standard deviation than Comparative Example 1. This confirms that the effect of flattening the film by ion irradiation can be obtained not only in the formation of a laminated film, but also in the formation of a single layer film.

Other Embodiments
The present invention is not limited to the above-described embodiment, but also includes other embodiments shown below. The present invention also includes a combination of all or any of the above-described embodiment and the other embodiments shown below. Furthermore, these embodiments can be omitted, replaced, or modified in various ways without departing from the scope of the invention, and such modifications are also included in the present invention.

(1) In the above embodiment, as shown in FIG. 1, the turntable 31 rotates counterclockwise in plan view, but it may be rotated clockwise if the ion irradiation unit 60 irradiates ions onto the film in the process of being formed after the film formation by the film formation processing unit 40 and before the film formation by the film formation processing unit 40 is performed again. In other words, the transport unit 30 is configured to enable cyclic transport in two directions, and the film processing unit 50 and the ion irradiation unit 60 may be provided adjacent to each other. This makes it possible to switch the order of the chemical reaction by the film processing unit 50 and the film planarization process by the ion irradiation unit 60.

(2) In the above embodiment, the conveying unit 30 circulates the workpiece 10 through the film forming unit 40, the film processing unit 50, and the ion irradiation unit 60 in that order. However, the order of the film processing unit 50 and the ion irradiation unit 60 may be reversed to circulate the workpiece 10 through the film forming unit 40, the ion irradiation unit 60, and the film processing unit 50 in that order while maintaining the same rotation direction (counterclockwise) as in the above embodiment. In the former case, as in the above embodiment, the film after the chemical reaction by the film processing unit 50 can be irradiated with ions to flatten the film. In the latter case, the oxygen atoms or nitrogen atoms separated from the compound film by ion irradiation in the ion irradiation unit 60 can be replenished by the film processing unit 50 that passes next by containing oxygen gas or nitrogen gas in the processing space 59 of the film processing unit 50.

(3) In the above embodiment, the conveying unit 30 has a rotating table 31, but instead of the rotating table 31, an arm extending radially from the center of rotation may be used. In this case, the arm rotates while holding the tray 34 or the workpiece 10.

(4) The film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60 may be located on the bottom side of the chamber 20, and the up-down relationship between the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60 and the rotating table 31 may be reversed. In this case, the surface of the rotating table 31 on which the tray 34 is arranged is the surface that faces downward when the rotating table 31 is horizontal, i.e., the bottom surface.

(5) The installation surface of the film forming apparatus 100 may be a floor surface, a ceiling, or a side wall surface. In the above embodiment, the tray 34 is provided on the upper surface of the horizontally arranged turntable 31, the turntable 31 is rotated in a horizontal plane, and the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60 are arranged above the turntable 31, but this is not limited to the above. For example, the arrangement of the turntable 31 may be vertical or inclined, not limited to horizontal. In addition, the tray 34 may be provided on opposite surfaces (both surfaces) of the turntable 31. In other words, in the present invention, the direction of the rotation plane of the conveying unit 30 may be any direction, and the positions of the tray 34, the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60 may be positions where the workpiece 10 held on the tray 34 can be processed by the film forming processing unit 40, the film processing unit 50, and the ion irradiation unit 60.

10 Work 11 SiO ₂ film 12 Nb ₂ O ₅ film 20 Chamber 20a Ceiling 20b Inner bottom surface 20c Inner circumferential surface 21 Exhaust port 21a Opening 22 Partition section 30 Transport section 31 Rotary table 32 Motor 33 Holding section 34 Tray 40, 40a, 40b Film forming processing section 41 Processing space 42 Target 43 Backing plate 44 Electrode 46 Power supply section 47 Gas inlet 48 Pipe 49 Sputtering gas inlet 50 Film processing section 51 Cylindrical body 52 Window member 53 Antenna 54 RF power supply 55 Matching box 56 Gas inlet 57 Pipe 58 Process gas inlet 59 Processing space 60 Ion irradiation section 61 Cylindrical electrode 61a Opening 61b Flange 62 Insulating member 63 Housing 64 Shield 65 Process gas inlet 66 RF power supply 67 Matching box 70 Load lock unit 80 Control device 90 Exhaust unit 100 Film forming device G1 Sputtering gas G2 Process gas G3 Process gas

Claims (9)

A film forming apparatus for forming a film on a workpiece,
a chamber within which a vacuum can be created;
a conveying unit provided in the chamber and having a rotary table that circulates and conveys the workpiece along a circumferential conveying path;
a film forming processing section including a target made of a material constituting the film, and a plasma generator for generating plasma from a sputtering gas introduced between the target and the rotary table, and for sputtering the target with the plasma to form a film on the workpiece;
a film processing section including a cylindrical body that protrudes into an internal space of the chamber and opens toward the transfer path, a window member that is provided to close the opening of the cylindrical body, a first process gas inlet section that introduces a first process gas into a processing space formed between the turntable and the cylindrical body, an antenna that generates an electric field in the processing space via the window member, and a power source that applies a high frequency voltage to the antenna, the first process gas being converted into plasma to generate an inductively coupled plasma in the processing space, and causing a chemical reaction of the film;
a cylindrical electrode having an opening at one end and attached to the chamber such that the opening faces the transfer path; a second process gas inlet section for introducing a second process gas into the cylindrical electrode; an ion irradiation section for irradiating the film with ions generated by plasmatizing the second process gas, the ion irradiation section having a power source connected to the turntable and the cylindrical electrode, the power source connected to the turntable and the cylindrical electrode, the power source applying a high frequency voltage to the cylindrical electrode;
Equipped with
The transport unit circulates and transports the workpiece so that the workpiece passes through the film formation processing unit, the film processing unit, and the ion irradiation unit,
the ion irradiation unit irradiates the film in the process of being formed on the workpiece with ions to flatten the film ;
A film forming apparatus characterized by the above. The transport unit transports the workpiece so that the workpiece passes through the film treatment unit and then passes through the ion irradiation unit;
2. The film forming apparatus according to claim 1, The transport unit transports the workpiece so that the workpiece passes through the ion irradiation unit and then passes through the film treatment unit;
2. The film forming apparatus according to claim 1, The transport unit is configured to be capable of the circulating transport in two directions,
The film processing unit and the ion irradiation unit are provided adjacent to each other.
4. The film forming apparatus according to claim 2 or 3, the first process gas contains oxygen or nitrogen;
5. The film forming apparatus according to claim 1, wherein: A plurality of the film forming processing units are provided,
The plurality of film forming processing units form the films having different compositions on the work by alternately stacking the films;
6. The film forming apparatus according to claim 1, wherein: the second process gas comprises argon;
7. The film forming apparatus according to claim 1, wherein: the second process gas comprises oxygen or nitrogen, or argon and oxygen or nitrogen;
7. The film forming apparatus according to claim 1, wherein: The rotary table rotates around a rotation axis to circulate the workpiece,
9. The film forming apparatus according to claim 1, wherein the rotation axis and a surface of the rotary table on which the work is placed are perpendicular to each other.

Images